A non-interventional naturalistic study of the prescription patterns of antipsychotics in patients with schizophrenia from the Spanish province of Tarragona

© 2015 Gaviria et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Background: The analysis of prescribing patterns in entire catchment areas contributes to global mapping of the use of antipsychotics and may improve treatment outcomes. Objective To determine the pattern of long-term antipsychotic prescription in outpatients with schizophrenia in the province of Tarragona (Catalonia-Spain). Methods: A naturalistic, observational, retrospective, non-interventional study based on the analysis of registries of computerized medical records from an anonymized database of 1,765 patients with schizophrenia treated between 2011 and 2013. Results: The most used antipsychotic was risperidone, identified in 463 (26.3%) patients, followed by olanzapine in 249 (14.1%), paliperidone in 225 (12.7%), zuclopenthixol in 201 (11.4%), quetiapine in 141 (8%), aripiprazole in 100 (5.7%), and clozapine in 100 (5.7%). Almost 8 out of 10 patients (79.3%) were treated with atypical or second-generation antipsychotics. Long-acting injectable (LAI) formulations were used in 44.8% of patients. Antipsychotics were generally prescribed in their recommended doses, with clozapine, ziprasidone, LAI paliperidone, and LAI risperidone being prescribed at the higher end of their therapeutic ranges. Almost 7 out of 10 patients (69.6%) were on antipsychotic polypharmacy, and 81.4% were on psychiatric medications aside from antipsychotics. Being prescribed quetiapine (OR 14.24, 95% CI 4.94-40.97), LAI (OR 9.99, 95% CI 6.45-15.45), psychiatric co-medications (OR 4.25, 95% CI 2.72-6.64), and paliperidone (OR 3.13, 95% CI 1.2